GTA: Civilization Wars

A long time ago, there was a powerful civilization that stood up above the rest. It was the most powerful civilization that non-other can compete to it. However, its own power destroy it. Now, other civilizations want the power for their own and they would conquer anything that stand up against them.
The game is played with a mouse and the idea here is to conquer one civilization after another. Once you conquered a building, the number of people you have grew within it and you can use that number to seize another building. Your enemy is also doing the same, so you need to conquer it as fast as you can.